1. Field of the Invention
This invention relates to a process for the preparation of cobalt (II) acetylacetonate. In this process, a cobalt compound is reacted with acetylacetonate at elevated temperature in the presence of a specific organic solvent at a reaction temperature which does not need to exceed 100.degree. C.
2. Discussion of Prior Art
It is known to prepare cobalt (II) acetylacetonate by reacting cobalt (II) compounds with acetylacetone. Suitable cobalt compounds are the salts of inorganic acids, such as the chloride, sulfate, nitrate, carbonate or also the hydroxide. Cobalt oxide, too, is suited for use. The reaction is carried out in an aqueous medium. Neutralization must be effected with ammonia or another weak base.
This procedure yields a product which contains two moles of water of crystallization in bound form. Elimination of the water is costly since it has to be carried out at reduced pressure (between 20 and 2 millibars) and at temperatures of up to 90.degree. C. A further drawback of this procedure is that the dry product is highly particulate and readily disintegrates to dust.
Thus, there has been a need to provide anhydrous cobalt (II) acetylacetonate in such a way that neutralization with ammonia and the onerous washing of the crude product can be dispensed with. Moreover, there has been a need for a process yielding a product that can readily be dried to an anhydrous state.